<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        td{
            border: 1px solid black;
        }
    </style>
    <script>
        // BOM对象: 警告框,通过浏览器打开一个警告框
        //alert()
        // DOM对象: 向body标签中输出内容
        document.write("<h1 align='center'>99乘法表</h1>");
        document.write("<table align='center'>");
        for (let i=1;i<=9;i++){
            document.write("<tr>");
            for (let j=1;j<=i;j++){
                document.write("<td>"+j+" * "+i+" = "+(i*j)+"</td>")
            }
            document.write("</tr>");
        }
        document.write("</table>");


    </script>
</head>
<body>

</body>
</html>